Hyperostotic tympanic bone spicules in domestic and wild animal species

Hyperostotic tympanic bone spicules (HTBS), or "mucoperiosteal exostoses" (ME, syn.) are small, globular (>= 1 mm in diameter), mostly stalked and drumstick-like, bony structures, which arise from the inner wall of the tympanic bulla and project into the middle ear cavity. HTBS present as mineral densities inside the tympanic bulla on radiographs or computed tomographic (CT) images. They have previously been referred to as "otoliths" and were thought to represent mineral concretions secondary to otitis media. Recently, it was shown that HTBS actually consist of regularly composed bone tissue, covered by normal middle ear mucosa. So far, HTBS have only extensively been described in dogs, where they occur with a prevalence of up to >45%. A recent study detected ME, most likely representing HTBS, in the tympanic cavities of skeletonised skull bones of African lions. To estimate the occurrence of HTBS in other mammal species, the middle ears of adult animals of 78 different domestic, wild, and zoo species undergoing routine necropsy at the Institute of Veterinary Pathology of the LMU Munich, Germany were examined in the present study. HTBS were found in the tympanic bullae of carnivorous species, such as canids (wolf, fox), and in several large felid species (lion, tiger, leopard, cheetah). In contrast, HTBS were not present in domestic cats (more than to 200 cases), small carnivorous species such as mustelids, nor in any primate, ungulate, ruminant, pig, insectivore, or rodent species. The detectability of HTBS by CT of the tympanic bullae of large felids was demonstrated in an African lion. Histologically, HTBS consisted of mature lamellar bone, covered by periosteum and a partially ciliated, flat epithelium, regularly without any apparent inflammatory alterations. The present study demonstrates that HTBS may frequently occur in large felids and in different canid species. These findings should be taken into account when examining the middle ear, or interpreting bulla radiographs/CT-images of the respective species. However, the factors triggering the development of HTBS remain to be identified

Goldstone bosons and a dynamical Higgs field

Higgs inflation uses the gauge variant Higgs field as the inflaton. During inflation the Higgs field is displaced from its minimum, which results in associated Goldstone bosons that are apparently massive. Working in a minimally coupled U(1) toy model, we use the closed-time-path formalism to show that these Goldstone bosons do contribute to the one-loop effective action. Therefore the computation in unitary gauge gives incorrect results. Our expression for the effective action is gauge invariant upon using the background equations of motion.Comment: 27 pages, 2 figures, published version with minor correction

Microstrip superconducting quantum interference device amplifiers with submicron Josephson junctions: enhanced gain at gigahertz frequencies

We present measurements of an amplifier based on a dc superconducting quantum interference device (SQUID) with submicron Al-AlOx-Al Josephson junctions. The small junction size reduces their self-capacitance and allows for the use of relatively large resistive shunts while maintaining nonhysteretic operation. This leads to an enhancement of the SQUID transfer function compared to SQUIDs with micron-scale junctions. The device layout is modified from that of a conventional SQUID to allow for coupling signals into the amplifier with a substantial mutual inductance for a relatively short microstrip coil. Measurements at 310 mK exhibit gain of 32 dB at 1.55 GHz.Comment: Version with high resolution figures at: http://physics.syr.edu/~bplourde/bltp-publications.ht

Picovoltmeter for probing vortex dynamics in a single weak-pinning Corbino channel

We have developed a picovoltmeter using a Nb dc Superconducting QUantum Interference Device (SQUID) for measuring the flux-flow voltage from a small number of vortices moving through a submicron weak-pinning superconducting channel. We have applied this picovoltmeter to measure the vortex response in a single channel arranged in a circle on a Corbino disk geometry. The circular channel allows the vortices to follow closed orbits without encountering any sample edges, thus eliminating the influence of entry barriers.Comment: 4 pages, 3 figures, submitted to Review of Scientific Instrument

PkANN - I. Non-linear matter power spectrum interpolation through artificial neural networks

We investigate the interpolation of power spectra of matter fluctuations using Artificial Neural Network (PkANN). We present a new approach to confront small-scale non-linearities in the power spectrum of matter fluctuations. This ever-present and pernicious uncertainty is often the Achilles' heel in cosmological studies and must be reduced if we are to see the advent of precision cosmology in the late-time Universe. We show that an optimally trained artificial neural network (ANN), when presented with a set of cosmological parameters (Omega_m h^2, Omega_b h^2, n_s, w_0, sigma_8, m_nu and redshift z), can provide a worst-case error <=1 per cent (for z<=2) fit to the non-linear matter power spectrum deduced through N-body simulations, for modes up to k<=0.7 h/Mpc. Our power spectrum interpolator is accurate over the entire parameter space. This is a significant improvement over some of the current matter power spectrum calculators. In this paper, we detail how an accurate interpolation of the matter power spectrum is achievable with only a sparsely sampled grid of cosmological parameters. Unlike large-scale N-body simulations which are computationally expensive and/or infeasible, a well-trained ANN can be an extremely quick and reliable tool in interpreting cosmological observations and parameter estimation. This paper is the first in a series. In this method paper, we generate the non-linear matter power spectra using HaloFit and use them as mock observations to train the ANN. This work sets the foundation for Paper II, where a suite of N-body simulations will be used to compute the non-linear matter power spectra at sub-per cent accuracy, in the quasi-non-linear regime 0.1 h/Mpc <= k <= 0.9 h/Mpc. A trained ANN based on this N-body suite will be released for the scientific community.Comment: 12 pages, 9 figures, 2 tables, updated to match version accepted by MNRA

Gibt es einen Zusammenhang zwischen der Keimzahl von Staphylococcus aureus im Nasenvorhof und dem Risiko für Infektionen durch den Erreger?

S. aureus ist als Erreger ambulant und nosokomial erworbener Infektionen von herausragender Bedeutung. Eine zentrale Rolle für die Pathogenese von S. aureus-Infektionen wird dem endogenen Infektionsweg zugeschrieben. Die vorliegende Studie ging der Frage einer Korrelation zwischen dem quantitativen Ausmaß einer mittels Keimzahlbestimmung determinierten S. aureus-Nasenvorhofbesiedlung und dem Risiko von S. aureus-Infektionen in einem Patientenkollektiv der Klinik für Thorax-, Herz-und Gefäßchirurgie des Universitätsklinikums Münster nach. Als entscheidende Determinante des Infektionsrisikos erwies sich nicht die Quantität der Nasenvorhofbesiedlung, sondern das Vorliegen einer nasalen S. aureus-Kolonisation an sich. Die Kenntnis von Risikofaktoren für eine Infektion ermöglicht durch Identifikation von Risikopatienten eine gezieltere Infektionsprävention. Die infektionsprophylaktische Wirkung der nasalen S. aureus-Eradikation mittels Mupirocin wird durch das Studienergebnis gestützt

Crystal growth and magnetic structure of MnBi2Te4

Millimeter-sized MnBi$_2$Te$_4$ single crystals are grown out of Bi-Te flux and characterized by measuring magnetic and transport properties, scanning tunneling microscope (STM) and spectroscopy (STS). The magnetic structure of MnBi$_2$Te$_4$ below T$_N$ is determined by powder and single crystal neutron diffraction measurements. Below T$_N$=24\,K, Mn$^{2+}$ moments order ferromagnetically in the \textit{ab} plane but antiferromagnetically along the crystallographic \textit{c} axis. The ordered moment is 4.04(13) $\mu_{B}$/Mn at 10\,K and aligned along the crystallographic \textit{c}-axis. The electrical resistivity drops upon cooling across T$_N$ or when going across the metamagnetic transition in increasing fields below T$_N$. A critical scattering effect was observed in the vicinity of T$_N$ in the temperature dependence of thermal conductivity. However, A linear temperature dependence was observed for thermopower in the temperature range 2K-300K without any anomaly around T$_N$. These indicate that the magnetic order in Mn-Te layer has negligible effect on the electronic band structure, which makes possible the realization of proposed topological properties in MnBi$_2$Te$_4$ after fine tuning of the electronic band structure

Intake of Dairy Products in Relation to Periodontitis in Older Danish Adults

This cross-sectional study investigates whether calcium intakes from dairy and non-dairy sources, and absolute intakes of various dairy products, are associated with periodontitis. The calcium intake (mg/day) of 135 older Danish adults was estimated by a diet history interview and divided into dairy and non-dairy calcium. Dairy food intake (g/day) was classified into four groups: milk, cheese, fermented foods and other foods. Periodontitis was defined as the number of teeth with attachment loss ≥3 mm. Intakes of total dairy calcium (Incidence-rate ratio (IRR) = 0.97; &lt;em&gt;p&lt;/em&gt; = 0.021), calcium from milk (IRR = 0.97; &lt;em&gt;p&lt;/em&gt; = 0.025) and fermented foods (IRR = 0.96; &lt;em&gt;p &lt;/em&gt;= 0.03) were inversely and significantly associated with periodontitis after adjustment for age, gender, education, sucrose intake, alcohol consumption, smoking, physical activity, vitamin D intake, heart disease, visits to the dentist, use of dental floss and bleeding on probing, but non-dairy calcium, calcium from cheese and other types of dairy food intakes were not. Total dairy foods (IRR = 0.96; &lt;em&gt;p&lt;/em&gt; = 0.003), milk (IRR = 0.96; &lt;em&gt;p&lt;/em&gt; = 0.028) and fermented foods intakes (IRR = 0.97; &lt;em&gt;p&lt;/em&gt; = 0.029) were associated with reduced risk of periodontitis, but cheese and other dairy foods intakes were not. These results suggest that dairy calcium, particularly from milk and fermented products, may protect against periodontitis. Prospective studies are required to confirm these findings